Bird cages are well known in the art. They house one or more birds and contain a wide variety of perches, swings, and amenities such as seed trays, gravel trays, water trays, baths, toys, and the like. For example, U.S. Pat. No. 2,693,786 discloses a bird cage having a door hingedly mounted at its bottom so that it may optionally be caused to assume either a closed or horizontal open position. When the door is in a fully open horizontal position, it is self-supporting providing the bird inside a takeoff and landing platform. One important consideration in bird cage design is the ease with which the cage may be cleaned. For example, U.S. Pat. No. 4,572,107 shows an easily cleanable animal enclosure consisting of a cage detachably positioned over a funnel supported by a base member. Newspaper is placed within the funnel to absorb excreted matter that is discharged from the cage. A detachable sack having an inner bag is placed at the bottom open end of the funnel to catch any excreted matter that falls through. U.S. Pat. No. 4,838,204 illustrates an animal cage assembly comprising a cage supported by a base having two opposite inwardly and downwardly sloping baffles which are spaced apart from one another to form a gap therebetween positioned below the cage and a tray located below the gap. Two paper roll holders are mounted adjacent their respective sloping baffles for providing paper which can be pulled across the baffles to periodically replace the paper on the baffles. U.S. Pat. No. Des. 77,845 shows a substantially triangular bird cage in the top plan view. U.S. Pat. No. Des. 224,934 shows an animal shelter having a pyramid shape. U.S. Pat. No. Des. 248,049 illustrates a triangular bird cage. And, U.S. Patent Des. 376,874 illustrates a wire bird cage having four inwardly sloping sides.